几种杀虫剂对香蕉黄胸蓟马的防治效果及其在香蕉果实中的残留

Control efficacy of several insecticides against Thrips hawaiiensis and their residue in banana fruits

黄胸蓟马是香蕉上的主要害虫之一,主要在花蕾内危害,传统施药方式效果不佳,而且近年来该虫已对香蕉上常用的吡虫啉等药剂产生了抗性,并导致了在香蕉果实中的残留问题,因此本研究于香蕉现蕾初期,采用香蕉花蕾注射方式,研究了施用溴虫氟苯双酰胺、双丙环虫酯、氟啶虫胺腈、氟啶虫酰胺、氯噻啉等新型药剂对香蕉蓟马的防效,并挑选防效较高的溴虫氟苯双酰胺和氯噻啉开展残留行为研究。结果表明:于香蕉现蕾初期,花蕾注射施用5%溴虫氟苯双酰胺悬浮剂1000倍液和40%氯噻啉水分散粒剂5000倍液各1次,溴虫氟苯双酰胺和氯噻啉对黄胸蓟马的防效分别达到84.7%和82.1%,在香蕉上的半衰期分别为8.1 d和8.0 d,且在最终采收时香蕉全果中两种农药的残留量均低于定量限(LOQ=0.005 mg/kg)。因此,可推荐采用香蕉花蕾注射的方式施用溴虫氟苯双酰胺和氯噻啉来防治香蕉黄胸蓟马。

Thrips hawaiiensis(Morgan)is one of the main pests on bananas and mainly harms the flower buds.Traditional application methods of pesticides were ineffective for this kind of thrips,and in recent years,the insects have developed resistance to imidacloprid and other commonly used insecticides,resulting in pesticide residue problems on banana fruits.In this study,the control efficacy of broflanilide,afidopyropen,sulfoxaflor,flonicamid and imidaclothiz against T.hawaiiensis were determined by bud injection of the pesticide formulations in the early stage of bud development of banana,and the residue behavior was analyzed for broflanilide and imidaclothiz,which both showed high control efficacy.Results showed that broflanilide and imidaclothiz had control efficiencies of 84.7%and 82.1%after bud injection at the early stage of budding with 5%broflanilide suspension concentrate at 1000-fold dilution and 40%imidaclothiz water dispersible granules at 5000-fold dilution,respectively.The half-lives of broflanilide and imidaclothiz on bananas were 8.1 d and 8.0 d,respectivery and the final residues were below the LOQ(0.005 mg/kg)in whole fruit of bananas.Therefore,broflanilide and imidaclothiz were recommended to be used on banana by bud injection method to control T.hawaiiensis.